The white flocculent sex attracting secretion produced by the male dung beetle, Kheper lamarcki MacLeay, was found to consist of tubular polypeptide fibres containing hexadecanoic acid, 2,6-dimethyl-5-heptenoic acid and (E)-nerolidol as major components, while a trace of skatole is responsible for the unpleasant odour of the secretion.

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The defensive osmeterial secretion of pre-final instar larvae of the citrus swallowtail,Papilio demodocus (Lepidoptera: Papilionidae) was found to contain methyl 3-hydroxybutanoate, 3-hydroxybutanoic acid, α-pinene, myrcene, limonene, β-phellandrene, (Z)-ocimene, (E)-ocimene, β-caryophyllene, (E)-β-farnesene, and germacrene-A, as well as a further number of unidentified sesquiterpenoid constituents. The presence of germacrene-A in the secretion was inferred from the formation of β-elemene under certain GC conditions. Larvae of the second, third, and fourth instars produce qualitatively similar secretions. Remarkable quantitative differences were found between the secretions of individual larvae. These variations could not be correlated with the diet on which the larvae were fed, their sex, instar, or color form. However, in a number of larvae the two prongs of the osmeterium were found to produce quantitatively different secretions.

Using gas chromatography with flame ionization detection (FID) and electroantennographic detection (EAD) in parallel, butanoic acid, skatole, and (E)-2,6-dimethyl-6-octen-2-ol were identified as constituents of the abdominal sexattracting secretion of the male dung beetle, Kheper subaeneus, which reproducibly elicited EAD responses in male and female antennae. This is the first report of the occurrence of (E)-2,6-dimethyl-6-octen-2-ol as a natural product, for which the name (E)-subaeneol is proposed. In some experiments, a few other constituents of the secretion also gave reproducible responses in specific male and female antennae but did not elicit responses when the analyses were repeated with other antennae. The major volatile constituent of the secretion, identified as (S)-(C)-2,6-dimethyl-5-heptenoic acid, is one of these EAD-active compounds. Both this compound and (E)-2,6-dimethyl-6-octen-2-ol were synthesized from authentic starting materials for comparison with the natural products.